password/voting ID

hello,

i am writing a program where someone enters their "password" into a gui and then can vote for some people. So far the voting part is working but the password is not. For the password, the user enters any number(s) and the program should store it into an array. After that, they can vote. When someone votes again they enter a new password and that password is entered as the second term of the array. If you enter the same password then an error message should show up. Heres my code:

1.) The array containing the passwords must not be created in the action listener because it handles multiple actions. It must be an instance variable of the class and the actionPerformed can check against it and add to it.
2.) If the array of passwords is not persisted then running the program again will always use a new array of passwords since all the program's data will go away when the application is closed.